G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Astronomia a neutrini con km 3 sott’acqua e ghiaccio

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Why neutrino astronomy? Neutrino astronomy aims at the identification of the sources of the UHECRs Neutrinos traverse space without being deflected or attenuated –They point back to their sources –They allow to view into dense environments Neutrinos are produced in high energy hadronic processes –They can allow distinction between hadronic and leptonic acceleration mechanisms Neutrinos traverse space without being deflected or attenuated –They point back to their sources –They allow to view into dense environments Neutrinos are produced in high energy hadronic processes –They can allow distinction between hadronic and leptonic acceleration mechanisms Absorption lenght of CR in the Universe

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Neutrino production in cosmic accelerators Proton acceleration Fermi mechanism proton spectrum dN p /dE ~E -2 Neutrino production proton interactions p  p (SNR,X-Ray Binaries) p   (AGN, GRB, microQSO) decay of pions and muons Astrophysical jet Particle accelerator electrons are responsible for gamma fluxes (synchrotron, IC)

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 00   Neutral pion produced in pp collisions may produce the observed TeV  fluxes (SNR RX J , Aharonian 2004,2005) HE proton interaction on ambient p or  Beam dump in gas dense environment (SNR) +-+- Muons and muon-neutrinos  HE proton SN shells, clouds,.. Shock wave Target protons Beam dump in astrophysical jet environment (GRB,AGN,microQSO) Shock waves Matter shells HE proton Target photons pions muons and neutrinos GRB (Waxman), AGN jets (Mannheim), microQSO (Levinson)

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The observation of TeV neutrino fluxes requires km 2 scale detectors neutrino muon Cherenkov light ~5000 PMT Connection to the shore neutrino atmospheric muon depth >3000m

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Candidate sources and expected events Diffuse fluxes GZK neutrinos0.5 / year GRB (Waxman) 50 / year AGN (thin) (Mannheim) few / year (thick)>100 / year Point-like sources GRB (030329) (Waxman) 1-10 / burst AGN (3C279) (Dermer) few / year Galactic SNR (Crab) (Protheroe) few / year Galactic MicroQuasar (Distefano) / year Neutrino flux Probability to produce a detectable muon (E µ >E min ) Earth transparency Expected events in a 1 km 2 detector

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Status of collaborations BAIKAL, AMANDA: taking data NESTOR, ANTARES, NEMO R&D:under construction ICECUBE: under construction (expected 2010) KM3NET – Meditteranean : EU Design Study AMANDA ICECUBE BAIKAL ANTARES 2400 m NESTOR 3800 m NEMO 3500 m

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Two neutrino telescopes GX339-4 SS433 Crab VELA South Pole Mediterranean In order to obtain the whole sky coverage 2 telescopes must be built The Galactic Centre is observable only from the Northern Hemisphere GX339-4 SS433 Crab VELA Galactic Centre HESS data

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 HESS Sources Observable only from the Mediterranean

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The largest detector up to date: AMANDA Optical Module AMANDA-II 19 strings 677 OMs Depth m Effective Area  10 4 m 2 (E   TeV) Angular resolution  2°

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Atmospheric neutrinos Atmospheric neutrinos is the background for cosmic neutrinos but in the same time an important calibration tool. Neutrinos up to a few 100 TeV have been observed in AMANDA  Spectrum can be used to search for E -2 component E 2  μ (E) < 2.9·10 –7 GeV cm -2 s -1 sr -1 Limit on diffuse E -2 ν μ flux ( TeV): horizontal vertical Hulth, NOVE 2006

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Point Source SearchSelected Sources SS Crab Nebula Cygnus X Cygnus X ES Markarian 421 Flux Upper Limit  90% (E >10 GeV) [10 -8 cm -2 s -1 ] Expected backgr. (4 years) Nr. of events (4 years) Source selected objects → no statistically significant effect observed … out of 33 Sources Systematic uncertainties under investigation Crab Nebula: MC probability to obtain an entry with at least this excess significance is 64% Sensitivity    ~2 for 200 days of “high-state” and spectral results from HEGRA Preliminary

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The future of underice neutrino telescope: ICECUBE The technology for underice detectors is reliable. The next step is the construction of the km3 detector ICECUBE. The technology for underice detectors is reliable. The next step is the construction of the km3 detector ICECUBE. 80 strings (60 PMT each) ” PMT (only downward looking) 125 m inter string distance 17 m spacing along a string Instrumented volume: 1 km 3 (1 Gton) First string deployed Jan 2005 IceCube will be able to identify  tracks from   for E > eV cascades from e for E > eV  for E > eV February strings deployed IceTop air shower array 80 pairs of ice Cherenkov tanks

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 ANTARES ANTARES is installing a 0.1 km 2 demonstrator detector close to Toulon 12 lines 25 storeys / line 3 PMTs / storey 900 PMTs ~70 m 350 m 100 m 14.5 m Submarine links Junction Box 40 km to shore Anchor/line socket to be deployed by ANTARES deployed Line 1 in February

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Operation (1st part) line 1 deployment Waiting in Foselev hangar since 15th december…loaded on 13th feb 2006

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 ANTARES Sea Operations

G. RiccobeneIFAE, Pavia 19-21Aprile 2006  Run Event   = 101 o  P(  2,ndf) = 0.88 t [ns] z [m] Antares preliminary Real Data: atmospheric muons reconstructed Result of Fit  Run Event   = 146 o  P(  2,ndf) = 0.61 t [ns] z [m]

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 NEMO The NEMO Collaboration is dedicating a special effort in: search, characterization and monitoring of a deep sea site adequate for the installation of the Mediterranean km 3 ; development of technologies for the km 3 (technical solutions chosen by small scale demonstrators are not directly scalable to a km 3 ). The NEMO Collaboration is dedicating a special effort in: search, characterization and monitoring of a deep sea site adequate for the installation of the Mediterranean km 3 ; development of technologies for the km 3 (technical solutions chosen by small scale demonstrators are not directly scalable to a km 3 ).

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The Capo Passero deep sea site The average depth is 3500 m, the distance from shore is 100 km. It is located in a wide abissal plateu far from shelf breaks and geologically stable. Optical properties of deep sea water are the best measured among investigated sites (absorption length close to optically pure water astro-ph\ ) Optical background is low (25 kHz on 10’’ PMT at 0.5 s.p.e. threshold) and mainly due to 40 K decay since the bioluminesce activity is extremely low. Underwater currents are very low (2.5 cm/s) and stable. After eight years of activity in seeking and monitoring abyssal sites in the Mediterranean Sea the NEMO collaboration has chosen the Capo Passero site. The site has been propsed to ApPEC on january 2003 as candidate site for the installation of the km 3.

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Absorption lengths measured in Capo Passero are close to the optically pure sea water data Differences between Toulon and Capo Passero are observed for the blue light absorption Seawater optical properties in Toulon and Capo Passero Optical properties have been measured in joint ANTARES-NEMO campaigns in Toulon and in Capo Passero (July-August 2002) NEMO data ANTARES data Average values 2850÷3250 m Light Absorption and attenuation lengths measured in Capo Passero don’t show seasonal dependence

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Optical background in Toulon and in Capo Passero Optical data measured in Capo passero are consistent with biological data: no luminescent bacteria have been observed in Capo Passero below 2500 m Optical background rate is much higher in Toulon.

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Present proposal for Detector Layout 1 main Junction Box 8  10 secondary Junction Boxes 60  80 towers 140  200 m between each tower 16  18 floors for each tower 64  72 PMT for each tower 4000  6000 PMTs NEMO will be modular detector: Main JB 1 st Secondary JB … N st Secondary JB 8  10 towers Changes: distances, number of towers, tower length, shape (hexagonal), … The tower geometry allows: good sensitivity to 100 GeV neutrinos A eff > 1 km 2 at E ~10 TeV feasibility of underwater operations

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Expected detector performaces Sensitivity Sensitivity to point like fluxes E v -2 spectrum NEMO81 towers 140m spaced PMTs IceCube80 strings 125m spaced PMTs Geometry “flexibility” Effective area for different detector geometries spacing towersfloors 140 m40 m 300 m40 m

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The NEMO Phase 1 The NEMO Collaboration is undergoing the Phase 1 of the project, installing a fully equipped deep-sea facility to test prototypes and develop new technologies for the km 3 detector. Shore laboratory port of Catania Underwater test site: 25 km E offshore Catania at 2000 m depth e.o. cable from shore TSS Frame To be completed in 2006 Junction Box NEMO mini-tower (4 floors) An electro-optical cable (10 fibres, 4 conductors) connects the shore laboratory, in the Port of Catania, with the underwater test site underwater e.o. cable

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The NEMO test site: a multidisciplinary laboratory The O DE station GEOSTAR SN-1 deep sea station First data from 2000 m GEOSTAR SN-1, a deep sea station for on-line seismic and environmental monitoring by INGV. The NEMO test site is the Italian site for ESONET (European Seafloor Observatory NETwork); O DE (Ocean noise Detection Experiment), for on-line deep sea acoustic signals monitoring (4 hydrophones hydrophones 30 Hz - 40 kHz  measurement of noise bkg for neutrino acoustic detection ).

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 NEMO Phase-1: scheme and deployment schedule 300 m Mini-Tower compacted Mini-Tower unfurled 15 m Deployment of JB and minitower summer 2006 Junction Box NEMO mini-tower (4 floors, 16 OM) TSS Frame Deployed january 2005

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The Junction Box Fiberglass external vessel Power vessels electro-optical connector The Junction Box hosts the data transmission and power distribution system This solution permits to separate the corriosion and the pressure resistance problems 1 m

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The tower Optical modules Floor control module Tower assembly at test site

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The NEMO Phase 2 project in Capo Passero Goals -Realization of an underwater infrastructure at 3500 m on the CP site -Test of the detector structure installation procedures at 3500 m -Installation of a 16 storey tower -Long term monitoring of the site Infrastructure -A building (1000 m 2 ) located inside the harbour area of Portopalo has been acquired. It will be renewed to host the shore station for power supply and data acquisition systems -100 km electro-optical cable (about 40 kW) purchsed. Deployment by Alcatel-Elettra. Project completion planned in 2007 Portopalo di Capo Passero

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 KM3NeT System and Product Engineering Information Technology Shore and deep-sea infrastructure Sea surface infrastructure Risk Assessment Quality Assurance Resource ExplorationAssociated Science Technical Design Report (and recommendation on installation site) WORK PACKAGES Partecipants: 34 istitutes from 8 countries Obiettivo: design study for a submarine high energy observatory open to multidisciplinary submarine science Start Finish Total Budget k €, UE funding 9000 k € Physics Analysis and simulations

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 Summary First generation detectors Baikal and AMANDA have demonstrated the feasibility of the high energy neutrino detection; The forthcoming km 3 neutrino telescopes will be “discovery” detectors with potential to solve HE astrophysics basic questions: UHECR sources, HE hadronic mechanisms, Dark matter... To fully exploit neutrino astronomy we need two km 3 scale detectors, one for each hemisphere; The under-ice km 3 ICECUBE is under way, following the AMANDA experience; The Mediterranean km 3 neutrino telescope will be an powerful astronomical observatory thanks to its excellent angular resolution; KM3Net feasibility study for the km3 detector started on beginning of 2006; ANTARES deployed Line1 on Feb. 2006, atmospheric muons already reconstructed; NEMO is installing the Test Site in Catania and building infrastructures in Capo Passero.

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 NEMO in Capo Passero

G. RiccobeneIFAE, Pavia 19-21Aprile 2006 The NEMO Collaboration INFN Bari, Bologna, Catania, Genova, LNF, LNS, Napoli, Pisa, Roma Università Bari, Bologna, Catania, Genova, Napoli, Pisa, Roma “La Sapienza” CNR Istituto di Oceanografia Fisica, La Spezia Istituto di Biologia del Mare, Venezia Istituto Sperimentale Talassografico, Messina Istituto Nazionale di Geofisica e Vulcanologia (INGV) Istituto Nazionale di Oceanografia e Geofisica Sperimentale (OGS) Istituto Superiore delle Comunicazioni e delle Tecnologie dell’Informazione (ISCTI) Circa 100 ricercatori dell ’ INFN e dei principali enti di ricerca italiani coinvoltii